AU700030B2

AU700030B2 - Self-emptying plug

Info

Publication number: AU700030B2
Application number: AU30611/95A
Authority: AU
Inventors: John Robert Liebert; Denis Alexander Miller; George Yammouni
Original assignee: SMARTPLUG Pty Ltd
Current assignee: SMARTPLUG Pty Ltd
Priority date: 1994-09-14
Filing date: 1995-09-14
Publication date: 1998-12-17
Anticipated expiration: 2015-09-14
Also published as: AU3061195A

Description

P/001011 28/5191 Reoulatioi .1,2

AUSTRALIA

Patents Act 1 990)

ORIGINAL

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4 a) .4 *4 -2- Field of the Invention This invention relates to a self-emptying plug for a container of liquid which plug is provided with a valve means which, when the hydrostatic pressure increases, depresses to allow emptying of the container when the pressure reaches a certain value.

Background of the Invention In this specification the word "container" is to be construed widely as meaning any vessel which can contain liquid and includes in particular bathtubs, spa baths, washing basins, laundry wash troughs and kitchen sinks.

There is a continuing problem concerning overfilling of containers such as baths.

This can cause particular problems where there is no arrangement to allow the removal of overflow water, for example, by means of a drain plug hole partly up the side of the container.

The self-emptying plug according to the invention provides at least a partial solution 15 to this problem in that it allows drainage of liquid once a given pressure is exceeded.

Brief Summary of the Invention This invention provides a self emptying plug for a container including: a) a plug body having an outlet for liquid, the plug body further including valve guide means; 20 b) a cap means adapted to fit over the plug body, the cap means having at least one liquid flow passage therein; c) valve seat means; d) valve means including a valve head and a valve stem, the valve stem being slidably received within the valve guide means and the valve head being adapted to bear against the valve seat means, said valve means being movable from a first position in which liquid cannot pass through said plug and a second portion I- 2ain which liquid can pass through said plug; e) spring means adapted to force the valve head against the valve seat means, the spring means being further adapted to deform at a selected hydrostatic pressure to allow movement of the valve means in a direction generally away from the first position, wherein the valve seat means includes at least a portion adapted to move with the valve head during an initial movement of the valve head in a direction generally away from the first position to thereby maintain the valve head in contact with the valve seat means during said initial movement.

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.4 i U Bs;"i i 2 Ocwbakw 9 3 BRIEF DESCRIPTION OF THE DRAWINGS: The accompanying drawings illustrate two embodiments of the invention in which: Fig I is an exploded view (as viewed down the page) of a first embodiment of a selfemptying plug; Fig 2 is a cross-sectional view of the assembled plug of Fig 1 in its "closed" configuration; Fig 3 is a cross-sectional view of the plug of Figs I and 2 in its "half-open" configuration; and Fig 4 is a cross-sectional view of the plug of Figs I to 3 in its "open" configuration.

Figure 5 is an exploded view (as viewed down the page) of a second embodiment of a self-emptying plug; Figure 6 is a cross-sectional view of the assembled plug of Figure 5 in its "closed" configuration; Figure 7 is a cross-sectional view of the plug of Figures 5 and 6 in its "halfopen" configuration; and Figure 8 is a cross-sectional view of the plug of Figures 5 to 7 in its "open" configuration.

DETAILED DESCRIPTION OF THE INVENTION: It is preferred that the plug body be adapted to fit into a plug seat which is itself adapted to fit into a hole in the container.

The plug seat may be let into the container either from its outside or its inside. The plug body and the plug seat are both preferably substantially round in shape. The plug body is preferably supplied with a grid through which liquid may flow, that is, the first outlet may comprise a number of holes. For example, the grid may be star-shaped having partitions extending from a central structure. The valve guide means is preferably located in the central structure. The valve guide means is preferably a hole extending through the central structure referred to above.

c- -1 I 7 x 7 4 The plug cap may be of any suitable shape but is preferably provided with a lip which fits down around the plug body, The second outlet may take the form of a number of holes of any suitable shape let through the top of the cap, the only requirement being that the holes allow a sufficient volume of liquid to flow therethrough.

The spring means may be of any suitable type, for example, a helical or a spiral spring specially adapted to collapse at a selected hydrostatic pressure. However, another option is a specially adapted flat plate spring. A preferred option is a Belville spring which, in a first operative position, is conically shaped (in cross-section) outwards but can take up a flattened shape (also in cross-section), in a second operative position.

The valve seat means is preferably adapted to flex downwardly and follow the direction of travel downwards of the valve head. For example, it may be constructed as a flexible, flat ring which can fit over the top of the plug body, be held within the upper region of the plug cap, or be retained between the plug cap and the plug body.

In a preferred embodiment, the self-emptying plug according to the invention may be provided with an override means which may be adapted to prevent opening of the valve means and/or close the valve means once open. For example, the plug body may be provided with a set of internal ramps arranged around the inside surface of the plug body. These ramps are adapted to interact with a set of runner means attached to or forming part of the valve means, whereby rotation of the valve means causes the runners to travel up the ramps forcing the valve means against the valve seat.

Alternatively, the cap may be provided with a pivoting hook or fork means which interacts with the upper end (as viewed in use) of the valve stem which may itself be suitably shaped to receive the pivoting hook or fork means. This example is suitable for prevention of opening of the valve means.

In another example, the override means incorporates a movable wedge means which may be shifted into and out of an operative position, forcing the valve head towards the valve seat or allowing it to move away from the valve seat.

In the second and third examples, the override means is operable from outside the plug cap and is preferably attached to or integral with the plug cap.

Turning to the accompanying drawings, in particular Fig 1: numeral I indicates a plug cap; numeral 2 indicates a valve seat; numeral 3 indicates a valve; numeral 4 indicates a Belville spring (in the flattened position); numeral 5 indicates a plug body; and numeral 6 indicates a plug seat.

Referring to plug cap 1, a pattern of outlets 10 is illustrated. Valve 3 is shown as having a valve head 11 and valve stem 12. Plug body 5 is shown with a centrally located valve guide 13 in a central structure 14 in a star-shaped grating 15 through which pass a number of outlets 16.

Plug body 5 comprises a narrow diameter, lower portion 17 joined to a wider diameter upper portion 18, A series of outer barbs 19 are shown on the outer surface of upper portion 18.

Finally, the plug seat 6 is provided with a base portion 20 and upstanding portion 21 which is adapted to fit snugly around plug body 5 using barbs 19 to improve fit.

h Turning to Figures 2 to 4, the diagrams themselves and the associated text indicates how, in a first operative position (Fig Belville spring 4 bears upwardly against valve head 11 I which in turn bears circumferentially against valve seat 2. Belville spring 4 in this position clearly has a conical cross-section. As hydrostatic pressure increases, valve 3 is forced downwardly and valve seat 2 flexes downwardly to follow valve head 11. Finally, as can be seen from Fig 4, Belville spring 4 collapses to allow valve head 1 I to leave contact with valve seat 2 and allow liquid to flow through the respective outlets 10 and 16, Note that in another embodiment barbs 19 may be left out and the desired snug fit between plug body 5 and plug seat 6 achieved by appropriate shaping of these components.

Referring to Figures 5 to 8: numeral 30 indicates a plug cap; numeral 31 indicates a valve seat; numeral 32 indicates an anti-flutter ring; numeral 33 indicates a valve;

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6 numeral 34 indicates a Belville spring (in the flattened position); numeral 35 indicates a plug body; and numeral 36 indicates a plug seat.

Referring to plug cap 30, a pattern of outlets 41 is illustrated. An eyelet 42 is formed on the top of plug cap 30 for use in attaching a chain.

Valve 33 is illustrated with a circular valve head 43 and a dependent valve stem 44. A twist bar is formed on the top (as viewed in use) of valve head 33. A set of outwardly projecting runners 46 is provided in the bottom (as viewed in use) of valve head 33.

Plug body 35 is shown with a centrally located valve guide 47 in a central structure 48 in a star shape grating 49 through which pass a number of outlets 50. Plug body 35 comprises a narrow diameter, lower portion 51 joined to a wider diameter upper portion 52. A series of stops 53 and ramps 54 are shown as formed on the inner surface of upper portion 52. Again, S *4 upper and lower outwardly projecting rings 55 are formed on the outer surface of upper portion 52, These rings are uLaful to fit plug body 35 into plug seat 36 and cap Plug seat 36 is provided with a base portion 56 and upstanding portion 57 which is adapted to fit snugly around plug body The purpose of stops 53 and ramps 54 is to force runners 46 on valve 33 to travel upwards and fit against the lower side of valve seat 31 closing the outlet, when twist bar 45 is rotated, 4*

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Referring to Figures 6 to 8, the valve operates as follows; a Figure 6 shows the valve as closed; Figure 7 shows the valve as it begins to open, the seat moves under water pressure to retain the seal; Figure 8 shows the seal breaks about 2.5mm through the stroke, the valve opens fully and water passes; and The fourth position (not shown) occurs when water head is reduced sufficiently and the valve closes.

A

Claims

1. A self emptying plug for a container including: a) a plug body having an outlet for liquid, the plug body further including valve guide means; b) a cap means adapted to fit over the plug body, the cap means having at least one liquid flow passage therein; c) valve seat means; d) valve means including a valve head and a valve stem, the valve stem being slidably received within the valve guide means and the valve head being adapted to bear against the valve seat means, said valve means being movable from a first position in which liquid cannot pass through said plug and a second portion in which liquid can pass through said plug; e) spring means adapted to force the valve head against the valve seat means, the spring means being further adapted to deform at a selected hydrostatic pressure to allow movement of the valve means in a direction generally away from 15 the first position, wherein the valve seat means includes at least a portion adapted to move with the valve head during an initial movement of the valve head in a direction generally away from the first position to thereby maintain the valve head I; in contact with the valve seat means during said initial movement. t

2. A self emptying plug as claimed in claim 1 wherein said spring means comprises a Belville spring having a generally conical shape in a first operative position and a generally flattened shape in a second operative position.

3. A self emptying plug as claimed in claim 1 or claim 2 wherein the spring means deforms at a selected hydrostatic pressure to allow generally downward movement of the valve means and wherein the valve seat means includes at least a portion adapted to move downwardly with the valve head during an initial downward movement of the valve head to thereby maintain i'e valve head in contact Swith the valve seat means during said initial movement. OWN.NB2WSI n7 Oaber 99 u -8-

4. A self emptying plug as claimed in claim 3 wherein the valve seat means is adapted to flex downwardly during said initial movement.

A self emptying plug as claimed in any one of claims 1-4 wherein the valve seat means comprises a flexible, substantially flat ring.

6. A self emptying plug as claimed in claim 5 wherein the valve seat means bears against an underneath surface of the cap means when the valve means is in its uppermost position.

7. A self emptying plug as claimed in any one of the preceding claims wherein the valve seat means fits over the plug body. 10

8. A self emptying plug as claimed in any one of claims 1 to 6 wherein the en. valve seat means is held within an upper region of the cap means.

9. A self emptying plug as claimed in any one of claims 1 to 6 wherein the valve seat means is located between the plug body and the cap means. ft ft.

10. A self emptying plug as claimed in any one of the preceding claims further 15 including override means adapted to prevent opening of the valve means or to close the valve means one open.

11. A self emptying plug as claimed in claim 10 wherein said override means comprises at least one ramp arranged on an internal surface of the plug body, said at least one ramp co-operating with at least one projection on the valvu means whereby rotation of the valve means causes the at least one projection to travel up the at least one ramp to force the valve means into contact with the valve seat means. GWN;:NB:26341.SPC 27 October 1998 I ly -c-l killo--If-i-; -9-

12. A self emptying plug as claimed in claim 11 wherein the valve means includes an upwardly extending bar to facilitate rotation of the valve means.

13. A self emptying plug as claimed in any one of the preceding claims further including a plug seat for receiving the plug body, said plug seat adapted to be received in the hole of the container.

14. A self emptying plug as claimed in any one of claims 1 to 12 wherein the plug body is adapted to be received in the hole of the container.

A self emptying plug as claimed in any one of the preceding claims wherein the cap means includes a plurality of liquid flow passages. 10

16. A self emptying plug as claimed in any one of the preceding claims wherein 4:4 the valve guide means includes an elongate passageway positioned in a central portion of the plug body, the elongate passageway slidably receiving the valve stem.

17. A self emptying plug as claimed in claim 10 wherein the override means comprises a pivoting hook or fork means which interacts with an upper end of the 15 valve stem to thereby prevent opening of the valve means.

18. A self emptying plug as claimed in claim 10 wherein the override means includes a movable wedge means movable into and away from an operative position whereby in the operative position the movable wedge means forces the valve head towards the valve seat means.

19. A self emptying plug as claimed in any one of the preceding claims wherein the plug cap is provided with a lip which fits down around the plug body.

A self emptying plug as claimed in claim 1 wherein the spring means G iv U 1 WNB 6341SPC 27 October 199 10 comprises a helical or a spiral spring.

21. A self emptying plug as claimed in claim 1 wherein the spring means is a flat plate spring.

22. A self emptying plug substantially as hereinbefore described with reference to the accompanying drawings. DATED: 27 October 1998 CARTER SMITH BEADLE g. Patent Attorneys for the Applicant: :SMARTPLUG PTY LTD e* e e a P a 6SPC 27 O ob 1998